Re: Audio ducking not supported
It certainly can't hurt to try: Using DISM (Deployment Imaging Servicing and Management) and SFC (System File Checker) to Repair Windows 8 & 10
If that doesn't do it, I'd try completely uninstalling NVDA and reinstalling. I've got NVDA 2021.3 (right now 2021.3.1 is downloading) and NVDA + SHIFT + D cycles through the three ducking states without issue.
Brian - Windows 10, 64-Bit, Version 21H2, Build 19044
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